I think you can take the Realm vs. Realm war in DAOC as a good example, of how PS is going to be.
Battles with about 100 vs 100 players can become laggy if you have a weak PC.
Usually there will be small groups of squads beating each other up on the battlefield. But the big and powerfull outfits will organize alliances within their empires quickly.
As soon as an alliance starts its attack on an other empires' bases, everyone runs like hell to defend the attacked region and battles become very large. The real big raids usually take place at the weekend and you will be forced to defend your empire till 4 am. :-)
And PS is going to be much bigger and faster than DAOC because you dont have to kill monsters to level.
The empire with the better organization will win most battles, so commanders will become very important.
It is more than impressive when you see an army of 100+ players approaching your defense line.
PS: Pilots, better watch your back
